Databricks Databricks Certified Associate Developer for Apache Spark 3.0 Exam Prep
Certified Associate Developer for Apache Spark (Page 13 )

• In Spark, an executor is a JVM that can have multiple cores. Each task can consume some CPUs (spark.task.cpus).
• The executor’s resources are effectively partitioned into slots, where each slot can run one task. The number of slots per executor is roughly spark.executor.cores / spark.task.cpus.
• Therefore, multiple tasks can run in parallel within the same executor (via these slots). So the statement “Tasks run in parallel via slots” is correct.

• A: A slot is not another name for an executor; a slot is a unit inside an executor.
• B: There’s no requirement that there must be fewer executors than tasks; tasks can be scheduled over time across the available slots.
• C: An executor can run more than one core; it’s not limited to a single core.
• D: There isn’t a rule that there must be more slots than tasks; tasks can wait if slots aren’t available, and you can have equal or even fewer slots than concurrent tasks.

• T?o m?t Systems Manager Automation runbook d? ch?y l?nh kh?i d?ng l?i ?ng d?ng trên các EC2 instance.
• T?o m?t Amazon EventBridge rule ph?n ?ng khi CloudWatch alarm chuy?n sang tr?ng thái ALARM.
• Ð?t Automation runbook làm target c?a EventBridge rule.

1. Log c?a ?ng d?ng du?c ghi vào CloudWatch Logs.
2. CloudWatch alarm phát hi?n nhi?u l?i liên quan d?n vi?c restart.
3. Alarm chuy?n sang tr?ng thái ALARM.
4. EventBridge nh?n s? ki?n thay d?i tr?ng thái này.
5. EventBridge g?i Systems Manager Automation runbook.
6. Runbook restart ?ng d?ng trên các EC2 instance, không restart c? instance.

• A: SNS không tr?c ti?p g?i Systems Manager Automation runbook nhu m?t target native.
• B: Lambda có th? th?c hi?n vi?c restart, nhung ph?i t? x? lý vi?c xác d?nh instance và ch?y l?nh t? xa.
• C: Lambda ch? làm trung gian d? g?i runbook, không c?n thi?t vì EventBridge có th? g?i runbook tr?c ti?p.

• You can configure different pre-shared keys for different device groups.
• All cameras could use one key.
• All scanners could use another key.
• Each key can be associated with an appropriate role or access policy.

Correct sequence

1. Merge Sales_Region with Sales_Manager using an inner join

1. Merge Region_Manager with Manager using an inner join

1. Merge Sales_Region and Region_Manager using a right join as a new query

• A — If there is no demand, there should be no production.

• B — Not all sales equal profit.

• C — Stocking up on inventory is bad for business.

• D — All costs, except materials, are considered fixed.

• E — Departments should operate at full capacity regardless of bottlenecks.

• transform() — modifies every element in an array
• filter() — keeps elements matching a condition
• exists() — checks whether any element matches
• aggregate() — reduces array elements to one result

sql 
SELECT transform(scores, x -> x * 2) 
FROM student_scores;

• A is incorrect because higher-order functions are mainly useful for nested or complex data.
• B is incorrect because they do not convert logic into Python.
• D is incorrect because their purpose is not to fix slow built-in functions, but to process arrays or maps with custom logic.

• B. Versioned configuration files — Infrastructure is defined in machine-readable files and tracked in version control, allowing repeatable provisioning and change history.
• D. Docker files — Assuming “Doctor files” is a typo for Dockerfiles, a Dockerfile declaratively defines how to build a container image and is commonly considered infrastructure/configuration as code.

• A. Cloned virtual machine images — These are prebuilt infrastructure artifacts, but cloning an image is not itself a code-based infrastructure definition.
• C. Change management database records — A CMDB records information about infrastructure; it does not define or provision that infrastructure.

• The JSON files contain one billion items, so this is a big-data workload.
• PySpark uses Apache Spark’s distributed, parallel processing, allowing the data to be processed across multiple compute nodes.
• It can read and transform data directly from OneLake, helping minimize unnecessary data movement or duplication.
• A Fabric notebook can also support exploration and visualization, as well as Spark-based analytics and anomaly-detection workflows.

• Pandas is primarily in-memory and generally suited to smaller datasets. One billion records would be impractical on a typical single machine.
• A Power BI report with core visuals is appropriate for visualization and sharing, but it is not the best tool for large-scale transformation, parallel processing, or anomaly detection. It would normally consume prepared data rather than perform the entire workload.

• Create a CodeCommit repository in the secondary Region.
• Use CodeBuild to run a Git mirror operation from the primary repository to the secondary repository.
• Use EventBridge to detect relevant repository events, such as a pull request being merged.
• Invoke a Lambda function, which starts the CodeBuild project.

• B: Amazon S3 is object storage, not a Git repository that developers can use as a CodeCommit remote.
• C: CodeArtifact is intended for packages and artifacts, not source-code repository mirroring.
• D: An AWS Cloud9 environment is not an appropriate automated replication mechanism and would require manual or persistent infrastructure management.

• Dataset file: Use Import mode. Excel files are imported into Power BI, and the two Sales tables can be combined with Power Query.
• Report file: Use a live connection to the published dataset. This keeps the report separate from the dataset and avoids importing the data again.

• Report file: DirectQuery/live connection
• Dataset file: Import

• Determining ISP-assigned address space: Usually involves public reconnaissance, such as WHOIS or regional Internet registry information.
• Bypassing DNS sinkholing: Would require evidence that malicious domains are resolving outside the organization’s sinkhole controls.
• Achieving initial access: DNS log entries alone do not demonstrate compromise or entry.
• Exfiltrating data: DNS tunneling generally involves repeated queries containing encoded or unusually long data, not merely internal host discovery.

• A is correct: It establishes the revised dates and identifies the effect on the critical path.
• B is premature: Stakeholders should be informed after the impact has been assessed and the updated schedule is understood.
• C is not automatically appropriate: Fast-tracking may introduce additional risk and should be considered only after analyzing schedule options.
• D is premature: Adding resources may not resolve a dependency and could increase costs without addressing the actual constraint.

• IKE (Internet Key Exchange) negotiates the IPsec security association, including:

• ESP (Encapsulating Security Payload) protects the data after negotiation by providing encryption and optionally authentication.
• AH provides authentication and integrity but does not encrypt traffic.
• TLS is used for protocols such as HTTPS, not for negotiating IPsec parameters.

• Early units show relatively large time savings.
• Later units still take less time, but the reduction becomes progressively smaller.
• The curve therefore becomes flatter as production approaches 256 units.

• B: The reduction is not constant; learning normally diminishes over time.
• C: Time does not reduce at an increasing rate.
• D: A steady state may eventually be reached, but the question concerns the first 255 units while learning is still occurring.

• Operating profit is affected because transfer price determines internal sales revenue.
• Return on investment (ROI) is affected because ROI depends partly on operating profit.
• Sales revenue is affected because the division records revenue from transferring its output.
• Cost of components purchased is not affected by the transfer price. These are input costs paid to external suppliers and are based on the supplier’s price.

• Annual interest payments net of tax relief (A): future cash outflows for the issuer.
• Redemption value (B): the final cash outflow when the bond is redeemed.
• Market value now (C): the cash proceeds received now, acting as the initial cash flow in the IRR calculation.

• Remote and global work: Access is based on the approved device, not a specific office or geographic location.
• Seamless login: Users may not need to repeatedly enter credentials on a recognized device.
• Limited equipment: It uses devices employees already have rather than requiring separate hardware.

• Geotagging: Restricts access based on location and may prevent legitimate remote work.
• Smart cards: Require issuing and managing additional physical equipment.
• Time-based logins: Limit access by time and do not provide a seamless authentication experience.

• B — Sales staff will tender for riskier contracts:

• C — Sales staff will encroach on other territories:

• D — Sales staff will look for new jobs:

• A. Adjust resolution: Incorrect because an incompatible resolution usually causes no display, distortion, or an unsupported-mode message—not intermittent flickering.
• B. Swap the HDMI cable: Correct. Replacing the common, easily tested component is the appropriate troubleshooting step.
• C. Replace the projector: Incorrect because the issue also occurs with a monitor.
• D. Configure refresh rate: A mismatched refresh rate can cause visual problems, but the repeated flicker across displays points more strongly to the cable.

• A — Technical review by business owner: A business owner may approve the business impact, but a technical review is normally performed by technical personnel.
• C — Cost-benefit analysis after implementation: Cost-benefit analysis should occur before implementation to support the approval decision.
• D — Business continuity testing: This can be appropriate for major changes, but it is primarily part of business continuity and disaster recovery planning—not a universal change-management activity.

• D — Managers focus on keeping costs low in the short term to maximise profits.

• E — Managers are given incentives to meet or undercut budgets.

• F — Managers delegate responsibility simply to reduce their workload.

• True positive: The scan reports a vulnerability that really exists.
• False positive: The scan reports a vulnerability that does not exist.
• True negative: The scan correctly reports no vulnerability.
• False negative: The scan fails to detect a vulnerability that is actually present.

• Set credit quotas for an account or individual virtual warehouses.
• Define monitoring intervals.
• Trigger actions when usage reaches thresholds, such as sending notifications or suspending a warehouse.
• Help control unexpected warehouse spending.

• Account Usage: Provides historical usage and billing data; it does not enforce credit limits.
• Warehouse Limit Parameter: Not the Snowflake object used for account-wide credit controls.
• Credit Consumption Tracker: Not a standard Snowflake object.

• Relationship cardinality:

• Filter direction:

• Active versus inactive relationships: only active relationships automatically propagate filters.
• Blank or unmatched values: a fact-table value without a matching dimension row can create the model’s blank/unknown member.
• Uniqueness: the “one” side must contain unique values; duplicate keys generally belong on the “many” side.

• How quickly the vendor must respond to incidents or requests
• Availability or uptime requirements
• Resolution time targets
• Performance expectations and penalties for failing to meet them

• SOW (Statement of Work): Describes the work, deliverables, scope, and schedule.
• MOA (Memorandum of Agreement): Documents an agreement in which parties commit to specific responsibilities.
• MOU (Memorandum of Understanding): Records a general intention to cooperate; it may not be legally binding.

• Deterrent control: The signs warning that people may be filmed can discourage unauthorized or malicious activity. They do not directly stop the action; they influence behavior.
• Detective control: CCTV records or monitors activity so security personnel can identify events or investigate them afterward.

• Preventive: Stops an incident from occurring, such as access control.
• Corrective: Restores systems after an incident.
• Directive: Instructs people to behave in a certain way, such as a security policy.
• Compensating: An alternative control used when the preferred control is not feasible.

• Honeypots: Deliberately vulnerable or attractive systems designed to lure attackers. Legitimate users should not access them, so activity on a honeypot is a strong indicator of compromise.
• DNS sinkholes: Redirect requests for known malicious domains to a controlled internal system instead of allowing the connection. This can identify infected hosts attempting to contact command-and-control infrastructure.

• Tokenization: Replaces sensitive data with non-sensitive tokens; it protects data but does not primarily detect attackers.
• CI/CD: Automates software development and deployment processes.
• Threat modeling: Identifies potential threats and weaknesses before or during system design.
• Data obfuscation: Makes data harder to understand, but it is not an attacker-detection method.

1. Open the Offenses tab

1. Open the offense details

1. Review contributing events

1. Analyze the attack chain

1. Investigate the assets

1. Validate and respond